1991 S10 Issues

Friendly format provided to inquire about automotive a/c systems.
Archived Forum

Moderators: bohica2xo, Tim, JohnHere

philipk1965
Posts: 7
Read the full article
Joined: Tue Jun 04, 2024 4:05 am

Re: 1991 S10 Issues

Post by philipk1965 »

UPDATE....

I put in 2 can of freon, pressures good L 32 H 133.

Works great now, Ice cold!
User avatar
Cusser
Preferred Member
Posts: 948
Joined: Sun Apr 24, 2016 6:29 am

Re: 1991 S10 Issues

Post by Cusser »

JohnHere wrote: Thu Jun 06, 2024 10:49 am If the low-side running PSI is approximately in the mid-20s to mid-30s, then the pressure switch on the accumulator should be "closed," or infinite ohms on a multimeter, which would cause the compressor to engage. If a correctly functioning pressure switch senses abnormally low or high pressure, it would "open," disengaging the compressor. So the zero ohms reading that you tested means the switch is "open."
I think JohnHere mixed this up.

"Closed" would be continuity or very few ohms resistance, likely less than 1 ohm.

"Open" would be infinite resistance, no continuity.



philipk1965 wrote: Wed Jun 12, 2024 5:56 am UPDATE....
I put in 2 can of freon, pressures good L 32 H 133.
Works great now, Ice cold!
Good, don't mess with it. By the way, the pressures you posted are semi-worthless without specifying rpm (typical pressures are read at about 2000 rpm) and outside/ambient temperature.
User avatar
JohnHere
Preferred Member
Posts: 1555
Joined: Sun May 13, 2018 10:20 am
Location: South Carolina Upstate - USA

Re: 1991 S10 Issues

Post by JohnHere »

Cusser wrote: Wed Jun 12, 2024 6:51 am JohnHere wrote: ↑Thu Jun 06, 2024 1:49 pm
If the low-side running PSI is approximately in the mid-20s to mid-30s, then the pressure switch on the accumulator should be "closed," or infinite ohms on a multimeter, which would cause the compressor to engage. If a correctly functioning pressure switch senses abnormally low or high pressure, it would "open," disengaging the compressor. So the zero ohms reading that you tested means the switch is "open."
I think JohnHere mixed this up.
"Closed" would be continuity or very few ohms resistance, likely less than 1 ohm.
"Open" would be infinite resistance, no continuity.
Of course! That's what I was trying to say :oops:
Member – MACS (Mobile Air Climate Systems Association)

Thankful for the responses you have received? Please consider making a monetary donation to this Forum.
philipk1965
Posts: 7
Joined: Tue Jun 04, 2024 4:05 am

Re: 1991 S10 Issues

Post by philipk1965 »

1800 RPM
Air temp 74 degrees F
relative humidity 54%
Post Reply